1. Field of the Invention
The present invention generally relates to a method for forming a semiconductor device. In particular, the present invention is directed to firstly carrying out a protective step to modify a first nitride material layer in the presence of oxygen, then carrying out a removal step to remove a second nitride material layer without substantially damaging the modified first nitride material layer. In such a way, the first nitride material layer may be free from slashing when the second nitride material layer is removed.
2. Description of the Prior Art
In the conventional semiconductor processes, it is proposed to increase the performance of a semiconductor element. Some general approaches are introduction of stress-boosting schemes to enhance the carrier mobility, new gate dielectric materials and/or new gate electrode materials.
However, those approaches all have drawbacks and may cause many collateral issues, such as they may make the manufacturing process more difficult and creates a lot of integration problems.
As a result, a novel semiconductor process is still needed to overcome the problems.